Adverse drug reactions

Question 1

What is an adverse drug reaction (ADR)?

Answer 1

A response to a medicinal product, or combination of medicinal products, which is noxious and unintended

Question 2

Define side effects?

Answer 2

an unintended effect of a drug related to its pharmacological properties and can include unexpected benefits of treatment

Question 3

What are examples of of mild ADRs?

Answer 3

nausea, drowsiness, itching rash

Question 4

What are examples of severe ADRs?

Answer 4

respiratory depression, neutropenia, catastrophic haemorrhage, anaphylaxis

Question 5

What is the first and secondary pharmacological effect of a beta blocker?

Answer 5

● Bradycardia and heart block are primary adverse effects
● Bronchospasm is a secondary pharmacological adverse effect

Question 6

What is the Rawlins Thompson classification of ADRs?

Answer 6

• Augmented
• Bizarre
• Chronic/continuing
• Delayed
• End of use/withdrawal
• Failure of treatment
• Genetic

Question 7

Describe augmented ADRs

Answer 7

• Most common type of ADR (80%)
• Exaggerated effect of drugs pharmacology at a therapeutic dose
• Often not life threatening
• Dose dependent and reversible upon withdrawing the drug

Question 8

Give an example of an augmented ADR

Answer 8

Bradycardia with betablockers

Question 9

Describe bizarre ADRs

Answer 9

• Not related to pharmacology of drug
• Not dose related
• Can cause serious illness or mortality
• Symptoms do not always resolve upon stopping drug

Question 10

Give an example of a bizarre ADR

Answer 10

Anaphylaxis with penicillin’s

Question 11

Describe chronic/continuing ADRs

Answer 11

ADRs that continue after the drug has been stopped

Question 12

Give an example of a chronic/continuing ADR

Answer 12

Osteonecrosis of the jaw with bisphosphonates

Question 13

Describe delayed ADRs

Answer 13

ADRs that become apparent some time after stopping the drug

Question 14

Give an example of a delayed ADR

Answer 14

Leucopenia with chemotherapy

Question 15

Describe end of use/withdrawal ADRs

Answer 15

ADR develops after the drug has been stopped

Question 16

Give an example of an end of use/withdrawal ADR

Answer 16

Rebound tachycardia after stopping beta-blocker

Question 17

Describe failure of treatment ADRs

Answer 17

• Unexpected treatment failure
• Could be due to drug-drug interaction or drug-food interaction
• Poor compliance with administration instructions

Question 18

Give an example of a failure of treatment ADR

Answer 18

Failure of bisphosphonate due to taking with food

Question 19

Describe genetic type ADRs

Answer 19

Drug causes irreversible damage to genome

Question 20

What is an example of a genetic ADR

Answer 20

Phocomelia in children of women taking thalidomide

Question 21

What is DoTS classification?

Answer 21

• An alternative way to classify ADRs
  
  • Dose-relatedness
  • Timing
  • Susceptibility

Question 22

What are the 3 categories for dose-relatedness in DoTS?

Answer 22

1. Hypersusceptibility
2. Collateral effects (side effects)
3. Toxic effects

Question 23

What is hypersusceptibility?

Answer 23

ADRs at subtherapeutic (smaller than normal) doses (eg anaphylaxis with penicillins)

Question 24

What are collateral effects?

Answer 24

ADRs at therapeutic doses (eg hypokalaemia with loop diuretic)

Question 25

What are toxic effects?

Answer 25

ADRs at subpratherapeutic (greater than normal) doses (eg liver damage with paracetamol)

Question 26

What are the 2 categories in timing in DoTS?

Answer 26

1. Time independent 2. Time dependent

Question 27

Describe time independent ADRs

Answer 27

ADRs which can develop during any time during treatment (often due to clinical changes in the patient)

Question 28

What are the categories of time dependent ADRs?

Answer 28

Rapid First dose Early Intermediate Late Delayed

Question 29

What does susceptibility mean in DoTS?

Answer 29

Certain patient groups/populations may have a specific susceptibility to ADRs from a drug

Question 30

What are the categories for susceptibility in DoTS?

Answer 30

- Age (anticholinergics in elderly patients) - Gender (metoclopramide in females) - Disease states (eg diclofenac in CVD) - Physiological states (eg phenytoin in pregnancy)

Question 31

What are ways to identify ADRs?

Answer 31

- Pre-clinical testing (computer models, cells and toxicity testing in animals) - Clinical trial data (pre-marketing evaluation) - Post marketing surveillance - Pharmacovigilance

Question 32

What is a black triangle medicine?

Answer 32

Medicines subject to post marketing surveillance are indicated by a black triangle

Question 33

Should ADRs be listed as a black triangle medicine?

Answer 33

All ADRs should be reported for Black triangle medicines

Question 34

What are causes for ADRs?

Answer 34

● Pharmaceutical variation ● Receptor abnormality ● Drug-drug interactions

Question 35

When would you suspect an ADR?

Answer 35

- Symptoms soon after a new drug is started - Symptoms after a dosage increase - Symptoms disappear when the drug is stopped - Symptoms reappear when the drug is restarted (rechallenge) - Patient concerns

Question 36

What are some common ADRs?

Answer 36

● Confusion ● Nausea ● Balance problems ● Diarrhoea ● Constipation ● Hypotension

Question 37

What is the yellow card scheme?

Answer 37

● The first ADR reporting scheme ● Collects spontaneous reports ● Acts as an ‘early warning system’ for identification of previously unrecognised reactions ● Provides information, about factors which predispose patients ADRs ● Continual safety monitoring of a product throughout its life span as a therapeutic agent

Question 38

Who are at increased risk to ADRs?

Answer 38

- Atopic individuals - Females - Children/neonates - Reduced drug clearance - Polypharmacy

Question 39

What are some serious ADRs?

Answer 39

- Caused hospitalisation - Prolonged hospitalisation - Life threatening - Causing disability or death - Causing congenital abnormalities - Deemed medically significant

Question 40

What 4 pieces of information would you include on a yellow card?

Answer 40

● Suspected drug ● Suspect reaction ● Patient details ● Reporter details